package com.zjt.takeoutproject.filter;

import com.alibaba.fastjson.JSON;
import com.zjt.takeoutproject.common.BaseContext;
import com.zjt.takeoutproject.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

//检查用户是否已经完成登录
@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {
    //路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;
        //1.获取本次请求URI
        String requestURI = request.getRequestURI();

        log.info("拦截到请求：{}",requestURI);

        String[] urls=new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/login",//移动端登录
                "/user/sendMsg",//移动端发送信息
                "/webjars/**",
                "/doc.html",
                "/swagger-resources",
                "/v2/api-docs"
        };

        //2.判断本次请求是否需要处理
        boolean check = check(urls, requestURI);
        //3.不需要处理的直接放行
        if (check){
            log.info("本次请求{}不需要处理",requestURI);
            filterChain.doFilter(request,response);
            return;
        }

        //4-1.判断登录状态，已登录的放行
        if(request.getSession().getAttribute("employee") != null){
            log.info("用户已登录，用户id为:{}",request.getSession().getAttribute("employee"));

            Long employeeId = (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(employeeId);

            filterChain.doFilter(request,response);
            return;
        }

        //4-2.判断移动端登录状态，已登录的放行
        if(request.getSession().getAttribute("user") != null){
            log.info("用户已登录，用户id为:{}",request.getSession().getAttribute("user"));

            Long userId = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);

            filterChain.doFilter(request,response);
            return;
        }

        log.info("用户未登录");
        //5.未登录则返回未登录结果,通过输出流方式向客户端响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;
    }

    //路径匹配，检查本次请求是否需要放行
    public boolean check(String[] urls,String requestURI ){
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if (match){
                return true;
            }
        }
        return false;
    }
}
